Our transcription: The Nineteenth and early Twentieth Centuries were the heyday of the amateur paleontologist or student of old life. These fossil hunters combing the cliff faces and quarries of the globe identified thousands of fossil species and painstakingly established their relative ages from the positions of the rock layers in which the fossils were entombed. Regardless of where on Earth fossils are found, they always occur in the same sequence relative to one another. Some of the lower rock strata in the Grand Canyon contain fossils of the same general groupings as those in certain varied ancient rock layers found in Wales. Since the ancient name for Wales is "Cambria," these rocks are called "Cambrian" rocks, and the geologic period in which they were formed, the "Cambrian" Period.